Under the Affordable Care Act, effective January 1, 2013, there is an increase in Medicare tax for certain high earners. An individual is liable for the additional tax to the extent his or her wages, other compensation, or self-employment income (together with that of his or her spouse if filing a joint return) exceed the following threshold amounts for the individual’s filing status:
| Filing Status | Threshold Amount |
| Married filing jointly | $250,000 |
| Married filing separately | $125,000 |
| Single | $200,000 |
| Head of household (with qualifying person) | $200,000 |
| Qualifying widow(er) with dependent child | $200,000 |
Read more here -
http://www.grafinsurance.com/wp-content/uploads/2012/05/Additional-Medicare-Tax-081612R.pdf